1. Field of the Invention
The present invention pertains to an automatic dosing-type dispenser for such products as toilet tank additives; for instance to bleaches, detergents, and dyes or the like. More specifically, the present invention is directed to a dispenser having no internal moving parts, but instead relying on movement of the whole apparatus to produce the necessary dispensing action.
2. Background Information
There has existed a long-standing need for dispensing a bleach, detergent and dye or the like on an automatic basis into a toilet bowl so as to be sure that such will be kept in a completely sanitary state, or at least to require very infrequent cleaning by the user.
A variety of approaches have been taken to meet this need. For example, one form of dispenser may be appreciated by reference to U.S. Pat. No. 3,504,384 to Radley et al issued Apr. 7, 1970. This patent discloses a duel dispenser for separately dispensing a detergent/dye solution and a hypochlorite (bleaching) solution into the flush water during the flushing operation. An important drawback of such scheme is that during the interval between flushes, relatively concentrated solutions of the bleach and detergent/dye compositions form in the respective dispensing chambers, and these solutions are discharged into the flush water on the next flushing operation. However, since the inlet and outlet ports of the dispensing chambers in the Radley et al dual dispenser are not closed between flushings, there is an opportunity for ingredients in the respective concentrated solutions in the chambers to diffuse into the tank water between flushes. Accordingly, there is also opportunity for ingredients from one dispensing chamber ultimately to find their way into the solution in the other dispensing chamber, and this is clearly undesirable since the dye will be rendered colorless in most cases and not provide its signalling function to the user.
In order to overcome the drawback in Radley et al, various proposals have been set forth in, for example, U.S. Pat. No. 3,831,205 in which there is disclosed an automatic dispensing apparatus for dispensing a solution formed from a solid material when the liquid level of a process stream e.g. level of tank water, drops below a predetermined level. However, such apparatus includes a float valve operative to dispense a needed amount of the solution into the flush tank at the end of a flush cycle. For reasons already indicated or which will become apparent, it is undesirable to include moving internal parts in a dispensing apparatus of this type since they are somewhat unreliable and shorten the life of the apparatus.
Other dosing dispensers known in the art are those disclosed in U.S. Pat. No. 4,171,546 in which a predetermined volume of a toilet tank additive solution is dispensed into a toilet tank as the water is draining therefrom; such dispensers comprising a reservoir in which a solid product is dissolved to form a product solution. However, such apparatus or device relies on vacuum transfer into the reservoir through an inlet conduit and relies on dispensing a dose volume of the product solution through a discharge standpipe. Such dispenser also provides an air lock when immersed in a full toilet tank so as to isolate the product and product solution from the toilet tank water surrounding the dispenser during quiescent periods; this patent also discloses the notion of co-dispensing several products into the toilet tank water.
Whatever the merits of the dispenser in the aforenoted U.S. Pat. No. 4,171,546, it will be appreciated that such involves a fairly complicated structure, although it does eliminate internal moving parts. Because of the complicated structure, however, a fairly expensive fabrication operation is called for to produce the dispenser, which is usually made of plastic.
Other patents that may be referred to for background material are: U.S. Pat. Nos. 4,186,856, 4,208,747, 4,036,407.
Whatever the particular construction, methods and advantages of the various reference devices or apparatus, it turns out that they do not fulfill the particular requirements and purposes of the present invention.
Accordingly, it is a primary object of the present invention to provide an automatic dispensing apparatus that will readily dispense either detergent or bleach, or both together, with provision for isolating each from the other in the latter case, and in any event, from the tank water.
Another primary object of the invention is to keep the bleach isolated from the entire body of liquid; that is, the tank water, during the quiescent periods between flushings; likewise, to keep the detergent/dye combination isolated from the tank water.
Yet another object is to provide a vastly simplified and inexpensive structure which will operate automatically in achieving the aforenoted objects.
Another object is to avoid the use of internal moving parts and to rely simply on the movement of the dispenser as a whole under appropriate conditions of mounting or positioning.
A further object is to enable ease of fabrication of the plastic dispensing apparatus.
Applicant's solution to the previously stated drawbacks and deficiencies in the prior art revolves around the exploitation of hydraulic and gravitational forces; specifically, of forces due to flotation of the dispenser in the tank water, and reliance on movement of the dispenser under the force of gravity when the liquid level drops in the tank.
It will of course be understood that it is generally known to rely on flotation and gravity in similar contexts. For example, Australian Pat. No. 222,793 discloses a liquid disinfectant dispensing device which utilizes buoyant or flotation means for holding a container in a first position when a tank or cistern is full, and for permitting a reservoir filled with liquid under that first condition to release its contents when the water level in the tank or cistern drops during a flushing cycle. Disclosures to somewhat the same effect: that is, disclosures of the same general principle or teaching may be obtained from the following references:
U.S. Pat. Nos. 1,365,642, 1,227,997, 2,644,167; PA1 British Pat. Nos. 946,812, 1,057,865.
Although the cited references pertaining to flotation means, or embodying flotation or buoyant principles, accomplish their own objects, they do not satisfy or fulfill the previously stated objects achieved by the present invention.